Rihanna has had a very, very busy week. You'd think that creating one of the most-buzzed-about events of New York Fashion Week — that would be the inclusive, dance-filled Savage x Fenty show — would be enough for her. But this is Rihanna we're talking about, so of course she didn't stop there. Instead, she took Thursday night to host her fourth annual Diamond Ball, an event she set up to benefit the Clara Lionel Foundation, the non-profit she founded in 2012.